1. Field of the Invention
The present invention relates to a video display stand, and more particularly to a video display stand having dual panning axes which is suitable for controlling a screen direction of appliances such as a TV set or a personal computer without bumping against a wall even in a state that it is positioned very closely to the wall, and its controlling method for automatically controlling screen directions by using a driving force.
2. Description of the Conventional Art
Generally, regarding a TV stand, for example, its screen direction is frequently desired to be changed according to viewing positions of a viewer.
Accordingly, if the TV stand would not be rotatable, the viewer should move the TV set whole to change its screen direction to desired positions for viewing, causing much inconvenience.
In an attempt to settle such inconvenience, a rotatable TV stand has been proposed.
FIG. 1 is a perspective view of a conventional TV set. As shown in the drawing, the TV set main body 1 is combined with a rotational support 2 which rotatably supports the TV from the bottom, so that the TV set can be rotated on the rotational support 2.
Such a general rotating apparatus has a single support, details of which will now be described with reference to FIGS. 2 and 3.
FIG. 2 is a plan view of the rotational support rotatably supporting the conventional TV set having a single support, and FIG. 3 is a sectional view showing a rotating support structure of the conventional TV set having the single support.
In the conventional TV set, as described above, a circular groove 3 is formed at a central portion of the rotational support 2. A combination hole 4 is formed at the center of the groove 3, and a circular rotation guide hole 5 having a constant radius centering the groove 3 is formed.
Corresponding to the rotational support 2, at a lower surface of the TV set main body 1, a rotational shaft 7 having a thread groove (not shown) is protrusively formed to be inserted into the groove 3 of the rotational support 2 and to be rotatably combined by being threaded with a screw 6 from the lower portion of the combination hole 4. A circular slide rib 8 is protrusively formed having a predetermined radius from the rotational shaft 7 and being inserted to the rotation guide groove 5 of the rotational support 2 so as to be slidably rotated centering the rotational shaft 7.
The TV set having such construction is rotatable 360xc2x0 centering the rotational shaft 7, of which the slide rib 8 is slidably rotated along the rotation guide groove 5 when the screen direction of the TV set is desired to be changed by the viewer.
In this respect, as shown in FIG. 4, in most cases, the TV set is positioned near the wall.
Thus, when the TV set is rotated to change its screen direction, since the right and left edges 9a and 9b of the rear portion of the receiver main body 1 touch the wall, its rotation range is much limited.
In addition, when the TV set is inadvertently turned while being laid near the wall, as shown in a dotted line of FIG. 4, the edges 9a and 9b of the rear portion 9 of the TV set main body 1 are readily bumped against the wall 10, possibly causing a breakdown to the main body or a damage to its internal components due to the impact.
Meanwhile, in view of rotating the TV set in desired directions as well as preventing such a damage to the main body, the TV set needs to be enough distanced from wall, which, however, would occupy much space, resulting in a problem of efficiency in space utilization.
Accordingly, an object of the present invention is to provide a video display stand having dual panning axes which can be suitably adopted for controlling screen directions of a TV set, or a personal computer as required to be changed at its own position, without bumping against a wall even when they are placed closely near the wall, and its controlling method for automatically controlling screen directions by using a driving force.
To achieve these and other advantages and in accordance with the purpose of the present invention, as embodied and broadly described herein, there is provided a video display stand having dual panning axes having a rotational base incorporatively or separatively formed at a lower surface of the video display stand and a rotation support member for supporting the rotational base, including: two motors being installed at a predetermined space, having a gear driving shaft at one side of either the rotational base or the rotation support member, each being driven to be rotated in a normal direction and in a reverse direction; two movement guide toothed slots each being formed along a circular arc centering a mutually opposite gear driving shaft with a predetermined width and depth at the opposite side corresponding to the position of each motor, and having a gear portion to be engaged with the gear driving shaft at one side of each wall; and a controller for controlling the driving of the motor.
There is also provided a method for controlling screen directions of a TV set for which two motors are selectively driven in a normal direction (clockwise) and in a reverse direction in accordance with a key operation by a user so that the TV set can be rotated rightward or leftward centering the driving shaft of each motor, including the steps of: judging whether the key input by the user is right turn command or left turn command, and a current screen direction of the TV set; driving a motor positioned at the opposite side to the key input command, of the two motors, in the normal direction or in the reverse rotation direction until the key input is released in case that the current TV set is directed to the front side or is placed in the same direction as the judged turn command; rotating a motor positioned at the side corresponding to the key input command, of the two motors, in the normal direction or in the reverse direction until the key input is released, in case that the TV set is placed in a different direction to the judged turn command; and stopping the rotation of the motor positioned at the side corresponding to the key input and then rotating the other motor in the same rotation direction as that of the corresponding motor until the key input is released, in case that the key input has not released yet even when the current TV set is already directed to the front side.